|
|
||||||||
BASIC SCIENCE INVESTIGATIONS |
Radionuclide Center Vrije Universiteit and Departments of Obstetrics and Gynecology, Otolaryngology, and Nuclear Medicine/PET Center, University Hospital Vrije Universiteit, Amsterdam, The Netherlands
A novel, facile procedure for efficient coupling of high doses of 131I to monoclonal antibodies (MAbs) was developed with minimal chemical and radiation damage. Methods: To diminish the radiation and chemical burden during labeling, iodination was performed in a large reaction volume and by temporarily coating the MAb with a minimal amount of IODO-GEN. The MAb was coated by injection of IODO-GEN (dissolved in acetonitrile [MeCN]) into the aqueous MAb solution, and the coating was subsequently removed by addition of ascorbic acid. For chemoprotection before, during, and after PD-10 purification of the 131I-MAbs, ascorbic acid and human serum albumin were used. The effects of autoradiolysis in the starting 131I solution were countered by treatment with NaOH and ascorbic acid. For this so-called IODO-GENcoated MAb method, the sensitive chimeric MAb MOv18 (c-MOv18) and the more robust murine MAbs K928 and E48 were used. The high-dose 131I-labeled MAbs were characterized for radiochemical purity and MAb integrity by thin-layer chromatography, high-performance liquid chromatography, and sodium dodecyl sulfate polyacrylamide gel electrophoresis followed by phosphor imager quantification. The high-dose 131I-labeled MAbs were also characterized for immunoreactivity. The radiopharmacokinetics and biodistribution of 131I-c-MOv18 were analyzed in human tumorbearing nude mice. For comparison, 131I-c-MOv18 batches were made using the conventional chloramine-T or IODO-GENcoated vial method. Results: Conventional high-dose labeling of 5 mg c-MOv18 with 4.4 GBq 131I resulted in a labeling yield of 60%, a radiochemical purity of 90%, an immunoreactive fraction of 25% (72% being the maximum in the assay used), and the presence of aggregation and degradation products. Using similar amounts of 131I and MAb in the IODO-GENcoated MAb method, 85%89% overall radiochemical yield, at least 99.7% radiochemical purity, and full preservation of MAb integrity and immunoreactivity were achieved. For this labeling, 5 mg MAb were coated with 35 µg IODO-GEN during 3 min in a reaction volume of 6 mL. Also, biodistribution was optimal, and tumor accumulation was superior to that of coinjected 125I-c-MOv18 labeled according to the conventional IODO-GENcoated vial method. Conclusion: A new, facile, high-dose 131I-labeling method was developed for production of 131I-labeled MAbs with optimal quality for use in clinical radioimmunotherapy.
Key Words: 131I labeling monoclonal antibody MOv18 IODO-GEN radioimmunotherapy immunoreactivity
This article has been cited by other articles:
![]() |
B. M. Tijink, T. Laeremans, M. Budde, M. S.-v. Walsum, T. Dreier, H. J. de Haard, C. R. Leemans, and G. A.M.S. van Dongen Improved tumor targeting of anti-epidermal growth factor receptor Nanobodies through albumin binding: taking advantage of modular Nanobody technology Mol. Cancer Ther., August 1, 2008; 7(8): 2288 - 2297. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Silacci, S. S. Brack, N. Spath, A. Buck, S. Hillinger, S. Arni, W. Weder, L. Zardi, and D. Neri Human monoclonal antibodies to domain C of tenascin-C selectively target solid tumors in vivo Protein Eng. Des. Sel., October 1, 2006; 19(10): 471 - 478. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. M. Tijink, D. Neri, C. R. Leemans, M. Budde, L. M. Dinkelborg, M. Stigter-van Walsum, L. Zardi, and G. A.M.S. van Dongen Radioimmunotherapy of Head and Neck Cancer Xenografts Using 131I-Labeled Antibody L19-SIP for Selective Targeting of Tumor Vasculature J. Nucl. Med., July 1, 2006; 47(7): 1127 - 1135. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. R. Perk, G. W.M. Visser, M. J.W.D. Vosjan, M. Stigter-van Walsum, B. M. Tijink, C. R. Leemans, and G. A.M.S. van Dongen 89Zr as a PET Surrogate Radioisotope for Scouting Biodistribution of the Therapeutic Radiometals 90Y and 177Lu in Tumor-Bearing Nude Mice After Coupling to the Internalizing Antibody Cetuximab J. Nucl. Med., November 1, 2005; 46(11): 1898 - 1906. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. O. Schaffland, F. Buchegger, M. Kosinski, C. Antonescu, C. Paschoud, C. Grannavel, R. Pellikka, and A. B. Delaloye 131I-Rituximab: Relationship Between Immunoreactivity and Specific Activity J. Nucl. Med., October 1, 2004; 45(10): 1784 - 1790. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Verel, G. W.M. Visser, R. Boellaard, M. Stigter-van Walsum, G. B. Snow, and G. A.M.S van Dongen 89Zr Immuno-PET: Comprehensive Procedures for the Production of 89Zr-Labeled Monoclonal Antibodies J. Nucl. Med., August 1, 2003; 44(8): 1271 - 1281. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| JOURNAL OF NUCLEAR MEDICINE TECHNOLOGY | THE JOURNAL OF NUCLEAR MEDICINE |